The present invention relates to interior rear view mirrors for motor vehicles, and is more particularly directed to an auxiliary mirror assembly which permits a vehicle operator to see into blind zones or voids in the mirror viewing area. This invention is more specifically concerned with an auxiliary mirror assembly that permits views to the sides into adjacent traffic lanes.
Vehicles are typically provided with an inside rear view mirror that provides a view to the rear through the vehicle rear window, an outside mirror mounted on the driver's side and another outside mirror mounted on the passenger's side of the vehicle. The inside mirror and the driver-side outside mirror are required to be of unit magnification (i.e., flat). Thus, their field of view is somewhat limited and there exist blind zones or blind spots in their coverage. Consequently, another vehicle travelling in an adjacent lane and a few feet behind the first vehicle would not be seen. The passenger-side outside mirror is often convex to provide wider coverage. However, in this type of mirror objects appear to be further from the vehicle than they in fact are, which can lead to errors in operator judgment. Also, even a convex mirror will not always reveal another vehicle in the blind zone.
Because of these blind zones or blind spots, collisions can occur when changing lanes, because a trailing vehicle in the next lane would not be detected in any of the mirrors. Consequently, for careful drivers, the practice of turning the head is required, to look out the side windows directly into the blind zone before maneuvering into the next lane. However, turning the head is unsafe as it requires looking away from the forward direction of travel. Also, for many drivers, turning the head can be painful or simply impossible.
Various extension mirrors have been proposed for seeing into blind zones, and a typical extension mirror is described in U.S. Pat. No. 4,598,982. There, an extension mirror is hinged to one side of a main inside rear view mirror, and can also be extended out laterally. However, because it is not possible to adjust the mirror angle, or to move the extension mirror up and down, or back and forth, it is difficult for the operator to position the main rear view mirror and any auxiliary mirrors to accommodate the operator's sitting position or to see clearly into blind zones to the left and right of the vehicle.